1. Field of the Invention
The present invention relates to a task chair with a support and with a seat that supports the buttocks and at least the part of the thigh near the buttocks.
2. Background Information
A conventional task chair has a standardized seat depth of approximately 40 to 43 cm. There is space on the seat surface for the buttocks and, depending on the size of the person sitting on the chair, a variable length of the thigh. For shorter persons, the front edge of the chair is often too far forward, so that the blood vessels in the legs are compressed by the front edge, thus hindering the blood supply to the legs. The unpleasant and unhealthy consequences are cold feet and varicose veins.
To correct the seat depth, in some task chairs, the position of the backrest is adjustable; that is, the person sitting in the chair can choose how great the distance between the front edge of the chair and the backrest should be. However, if the seat surface is physiologically shaped, then a shorter person sits too far forward or a tall person sits too far to the rear on the seat surface.
From German Patent DE 196 17 689 C (Faure), a seat depth adjustment for motor vehicle seats is known. In it, the seat region at the front of the seat is movable in the longitudinal direction of the vehicle. The front seat region is secured to the seat by two parallel retaining arms, which can be swivelled about a horizontal shaft fixed to the seat. Its top side is located partly under the seat surface. The retaining arms are articulated in the rear end of the moveable seat region, and a further, adjustable-length arm is pivotably secured to the seat at a rear shaft and articulated to the front end of the seat region. A disadvantage of this seat depth adjustment is that the retaining arms and the adjustable-length arm require shafts secured to the seat, which are disposed below and at a distance from the seat surface. Such a construction is unacceptable for task chairs for use in the office, because these arms under the seat surface are not only unattractive but do not guarantee enough space for the legs below the seat surface.